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Ying Y, Ma Y, Wang X, Wu J, Lin X, Li X, Yan J. Incineration-source fingerprints and emission spectrums of dioxins with diagnostic application. ENVIRONMENT INTERNATIONAL 2024; 188:108746. [PMID: 38776653 DOI: 10.1016/j.envint.2024.108746] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/15/2024] [Revised: 05/10/2024] [Accepted: 05/10/2024] [Indexed: 05/25/2024]
Abstract
Despite increasing waste-to-energy (WtE) capacities, there remain deficiencies in comprehension of 136 kinds of tetra- through octa-chlorinated dibenzo-p-dioxin and dibenzofurans (136 PCDD/Fs) originating from incineration sources. Samples from twenty typical WtE plants, encompassing coal-fired power plants (CPP), grate incinerators (GI), fluidized bed incinerators (FBI), and rotary kilns (RK), yielded extensive PCDD/F datasets. Research was conducted on fingerprint mapping, formation pathways, emission profiles, and diagnostic analysis of PCDD/Fs in WtE plants. Fingerprints revealed a prevalence of TCDF, followed by PeCDF, while CPP and RK respectively generated more PCDD and HxCDD. De novo synthesis was the predominant formation pathway except one plant, where CP-route dominated. DD/DF chlorination also facilitated PCDD/F formation, showing general trends of FBI > GI > CPP > RK. The PCDD/F emission intensities emitted in air pollution control system inlet (APCSI) and outlet (APCSO) followed the statistical sequence of RK > FBI > GI > CPP, with the average I-TEQ concentrations in APCSO reaching 0.18, 0.08, 0.11, and 0.04 ng I-TEQ·Nm-3. Emission spectrum were accordingly formed. Four clusters were segmented for diagnosis analysis, where PCDD/Fs in GI and FBI were similar, grouped as a single cluster. PCDD/Fs in CPP and RK demonstrated distinctive features in TCDD, HxCDD, and HxCDF. The WtE plants exceeding the limit value tended to generate and retain fewer TCDD and TCDF yet had higher fractions of HxCDD and HxCDF. The failure of APCS coupled with the intrinsic source strength of PCDD/Fs directly led to exceedance, highlighting safe operational practices. This study motivated source tracing and precise evaluation of 136 PCDD/Fs based on the revealed fingerprint profiles for WtE processes.
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Affiliation(s)
- Yuxuan Ying
- State Key Laboratory of Clean Energy Utilization, Institute of Thermal Power Engineering of Zhejiang University, Hangzhou 310027, China
| | - Yunfeng Ma
- School of Environment, Hangzhou Institute for Advanced Study, UCAS, Hangzhou 310024, China
| | - Xiaoxiao Wang
- State Key Laboratory of Clean Energy Utilization, Institute of Thermal Power Engineering of Zhejiang University, Hangzhou 310027, China
| | - Jiayao Wu
- State Key Laboratory of Clean Energy Utilization, Institute of Thermal Power Engineering of Zhejiang University, Hangzhou 310027, China
| | - Xiaoqing Lin
- State Key Laboratory of Clean Energy Utilization, Institute of Thermal Power Engineering of Zhejiang University, Hangzhou 310027, China.
| | - Xiaodong Li
- State Key Laboratory of Clean Energy Utilization, Institute of Thermal Power Engineering of Zhejiang University, Hangzhou 310027, China
| | - Jianhua Yan
- State Key Laboratory of Clean Energy Utilization, Institute of Thermal Power Engineering of Zhejiang University, Hangzhou 310027, China
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He F, Wang F, Peng Y, Cui H, Lv G. Insight into the formation of polychlorinated dibenzo-p-dioxins and dibenzofurans in hazardous waste incineration and incinerators: Formation process and reduction strategy. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2023; 345:118669. [PMID: 37506443 DOI: 10.1016/j.jenvman.2023.118669] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/16/2023] [Revised: 07/17/2023] [Accepted: 07/22/2023] [Indexed: 07/30/2023]
Abstract
Incineration technology has been widely adopted to safely dispose of hazardous waste (HW). While the incineration process causes the formation of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs). Due to its extreme toxicity, many scholars have been committed to determining the PCDD/F formation process and reducing emissions in incinerators. Previous studies ignored the impact of incineration and fluctuation of feeding materials on PCDD/F formation in hazardous waste incinerators (HWIs). In this study, differences in PCDD/F formation between HWIs and municipal solid waste incinerators (MSWIs) were pointed out. The incineration section in HWIs should be carefully considered. Laboratory experiments, conventional analysis and thermogravimetry experiments were conducted. An obvious disparity of PCDD/F formation between 12 kinds of HWs was found. Distillation residue was found with remarkably higher PCDD/F concentrations (11.57 ng/g). Except for the Cl content, aromatic rings and C-O bond organics were also found with high correlation coefficients with PCDD/F concentrations (>0.92). And PCDD/Fs were formed through a chlorination process and structure formation process. All of these are helpful to further understand the PCDD/F formation process during HW incineration, optimize the operation conditions in HWIs and reduce the emission pressure of PCDD/Fs in the future.
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Affiliation(s)
- Fengyu He
- Institute for Thermal Power Engineering, Zhejiang University, Hangzhou, 310027, China
| | - Fei Wang
- Institute for Thermal Power Engineering, Zhejiang University, Hangzhou, 310027, China.
| | - Yaqi Peng
- Institute for Thermal Power Engineering, Zhejiang University, Hangzhou, 310027, China
| | - Haibin Cui
- Institute for Thermal Power Engineering, Zhejiang University, Hangzhou, 310027, China
| | - Guojun Lv
- Institute for Thermal Power Engineering, Zhejiang University, Hangzhou, 310027, China
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Wang X, Lv J, Ying Y, Ma Y, Wu A, Lin X, Cao A, Li X, Yan J. A new insight into the CaO-induced inhibition pathways on PCDD/F formation: Metal passivation, dechlorination and hydroxide substitution. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 885:163782. [PMID: 37149162 DOI: 10.1016/j.scitotenv.2023.163782] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/23/2023] [Revised: 04/07/2023] [Accepted: 04/23/2023] [Indexed: 05/08/2023]
Abstract
Ca-based inhibitors (especially CaO) for PCDD/F (polychlorinated dibenzo-p-dioxin and dibenzofuran) formation are considered as economic inhibitors with low toxicity and strong adsorption of acidic gases (e.g., HCl, Cl2, and SOx), whereas the insight understanding of its inhibition mechanisms is scarcely explored. Herein, CaO was used to inhibit the de novo reaction for PCDD/F formation (250-450 °C). The evolution of key elements (C, Cl, Cu, and Ca) combined with theoretical calculations was systematically investigated. The concentrations and distribution of PCDD/Fs demonstrated the significant inhibition effect of CaO on I-TEQ (international toxic equivalency) concentrations of PCDD/Fs (inhibition efficiencies: > 90 %) and hepta~octa chlorinated congeners (inhibition efficiencies: 51.5-99.8 %). And the conditions (5-10 % CaO, 350 °C) were supposed to be the preferred conditions applied in real MSWIs (municipal solid waste incinerators). CaO significantly suppressed the chlorination of carbon matrix (superficial organic Cl (CCl) reduced from 16.5 % to 6.5-11.3 %) and the formation of unsaturated hydrocarbons or aromatic carbon (superficial CC decreased from 6.7 % to 1.3-2.1 %). Also, CaO promoted the dechlorination of Cu-based catalysts and Cl solidification (e.g., conversion of CuCl2 to CuO, and formation of CaCl2). The dechlorination phenomenon was validated by the dechlorination of highly chlorinated PCDD/F-congeners (via DD/DF chlorination pathways). Density functional theory calculations revealed that CaO facilitated the substitution of Cl by -OH on the benzene ring to inhibit the polycondensation of the chlorobenzene and chlorophenol (Gibbs free energy reduced from +74.83 to -36.62 and - 148.88 kJ/mol), which also indicates the dechlorination effect of CaO on de novo synthesis.
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Affiliation(s)
- Xiaoxiao Wang
- State Key Laboratory for Clean Energy Utilization, Institute for Thermal Power Engineering, Zhejiang University, Hangzhou 310027, China
| | - Jiabao Lv
- State Key Laboratory for Clean Energy Utilization, Institute for Thermal Power Engineering, Zhejiang University, Hangzhou 310027, China
| | - Yuxuan Ying
- State Key Laboratory for Clean Energy Utilization, Institute for Thermal Power Engineering, Zhejiang University, Hangzhou 310027, China
| | - Yunfeng Ma
- State Key Laboratory for Clean Energy Utilization, Institute for Thermal Power Engineering, Zhejiang University, Hangzhou 310027, China
| | - Angjian Wu
- State Key Laboratory for Clean Energy Utilization, Institute for Thermal Power Engineering, Zhejiang University, Hangzhou 310027, China; Jiaxing Research Institute, Zhejiang University, 314031, PR China
| | - Xiaoqing Lin
- State Key Laboratory for Clean Energy Utilization, Institute for Thermal Power Engineering, Zhejiang University, Hangzhou 310027, China; Jiaxing Research Institute, Zhejiang University, 314031, PR China.
| | - Ang Cao
- Department of Physics, Technical University of Denmark, 2800 Kongens Lyngby, Denmark
| | - Xiaodong Li
- State Key Laboratory for Clean Energy Utilization, Institute for Thermal Power Engineering, Zhejiang University, Hangzhou 310027, China; Jiaxing Research Institute, Zhejiang University, 314031, PR China
| | - Jianhua Yan
- State Key Laboratory for Clean Energy Utilization, Institute for Thermal Power Engineering, Zhejiang University, Hangzhou 310027, China
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Chen T, Xiang W, Wu A, Lin X, Chen Z, Li X, Yan J. Suppression on PCDD/Fs formation by a novel inhibition system consisting of phosphorous-based compounds coupled with a chlorine-deactivation material. WASTE MANAGEMENT (NEW YORK, N.Y.) 2023; 156:33-43. [PMID: 36436406 DOI: 10.1016/j.wasman.2022.11.026] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/10/2022] [Revised: 11/05/2022] [Accepted: 11/17/2022] [Indexed: 06/16/2023]
Abstract
The SN-containing inhibitors are effective for suppressing the formation of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) in the post-combustion zone of municipal solid waste incineration systems, but the industrial application of the SN-containing inhibitors is restricted by the high cost and the generation of corrosive by-products (e.g., SOx). To develop cost-effective and environmentally friendly inhibitors, a new inhibition system consisting of P-based compounds (i.e., NH4H2PO4 (ADP) and KH2PO4 (PDP)) and a chlorine-deactivation material (CaO) was proposed in this study. Also, the performance of this inhibition system in terms of suppressing PCDD/Fs formation was evaluated in an experimental system which simulated PCDD/Fs generation in the post-combustion zone. Generally, the formation of PCDD/Fs was effectively suppressed by over 95 % by the mixed inhibitors (ADP/CaO and PDP/CaO) and the individual inhibitor of ADP. Based on the observation on PCDD/F-fingerprints and the chemical speciation of Cl and Cu, the mechanisms of inhibitors were identified as: (i) passivating metal catalyst by converting the speciation of Cu from chlorides and Cu2+ with high reactivities to phosphates, oxides, and Cu+ with low reactivities, and (ii) deactivating Cl by CaO to prevent the formation of organic Cl which was critical for PCDD/Fs formation. In addition, both mechanisms were supported by (i) the better performance of inhibitors on suppressing the PCDD/F-congeners formed via de novo pathway than congeners synthesized from chlorophenols and (ii) lower degrees of chlorination of PCDD/Fs for reaction systems with CaO involved than other systems.
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Affiliation(s)
- Tong Chen
- State Key Laboratory of Clean Energy Utilization, Institute for Thermal Power Engineering, Zhejiang University, Hangzhou 310027, China
| | - Weican Xiang
- State Key Laboratory of Clean Energy Utilization, Institute for Thermal Power Engineering, Zhejiang University, Hangzhou 310027, China
| | - Angjian Wu
- State Key Laboratory of Clean Energy Utilization, Institute for Thermal Power Engineering, Zhejiang University, Hangzhou 310027, China
| | - Xiaoqing Lin
- State Key Laboratory of Clean Energy Utilization, Institute for Thermal Power Engineering, Zhejiang University, Hangzhou 310027, China.
| | - Zhiliang Chen
- Department of Civil and Environmental Engineering, Vanderbilt University, Nashville, TN 37235, USA.
| | - Xiaodong Li
- State Key Laboratory of Clean Energy Utilization, Institute for Thermal Power Engineering, Zhejiang University, Hangzhou 310027, China
| | - Jianhua Yan
- State Key Laboratory of Clean Energy Utilization, Institute for Thermal Power Engineering, Zhejiang University, Hangzhou 310027, China
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Lin X, Wang X, Ying Y, Wu A, Chen Z, Wang L, Yu H, Zhang H, Ruan A, Li X, Yan J. Formation pathways, gas-solid partitioning, and reaction kinetics of PCDD/Fs associated with baghouse filters operated at high temperatures: A case study. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 857:159551. [PMID: 36265614 DOI: 10.1016/j.scitotenv.2022.159551] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/21/2022] [Revised: 09/29/2022] [Accepted: 10/14/2022] [Indexed: 06/16/2023]
Abstract
The application of the 3T method during combustion (i.e., a Temperature > 850 °C, a residence Time > 2 s, and sufficient Turbulence) can lead to elevated operating temperature in the baghouse filter for the municipal solid waste incineration (MSWI) systems without sufficient heat exchange capacity, which is potentially detrimental to the emission control of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs). Herein, a field study focusing on the distribution and variation of PCDD/Fs in gaseous and solid phases in a baghouse filter with high operating temperature (225-230 °C) was carried out. The concentration of PCDD/Fs in gases at the outlet of the baghouse filter was around 1 order of magnitude higher than that in inlet gases (i.e., noticeable memory effect of PCDD/Fs), because of the significant PCDD/Fs formation in filter fly ash (primarily contributed by the precursor pathway) followed by PCDD/Fs desorption. In addition, the mechanisms and factors resulting in the memory effect of PCDD/Fs were identified based on a laboratory study that carefully investigated the formation and desorption of PCDD/Fs at potential operating temperatures of baghouse filters (i.e., 180, 200, and 225 °C). The temperature was identified as the key factor inducing the memory effect of PCDD/Fs, because: i) PCDD/Fs memory effect was not observed for baghouse filters with low operating temperatures of ~150 °C in previous studies; ii) both the formation and desorption of PCDD/Fs were noticeably favored by rising temperature from 180 to 225 °C; iii) increasing temperature appeared to facilitate the transformation from inorganic Cl to organic Cl and the conversion from aliphatic carbon to aromatic carbon or unsaturated hydrocarbons, both of which were favorable to PCDD/Fs formation; and iv) the release rate of PCDD/Fs from fly ash was exponentially dependent on temperature based on the modeling results of reaction kinetics.
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Affiliation(s)
- Xiaoqing Lin
- State Key Laboratory for Clean Energy Utilization, Institute for Thermal Power Engineering, Zhejiang University, Hangzhou 310027, China
| | - Xiaoxiao Wang
- State Key Laboratory for Clean Energy Utilization, Institute for Thermal Power Engineering, Zhejiang University, Hangzhou 310027, China
| | - Yuxuan Ying
- State Key Laboratory for Clean Energy Utilization, Institute for Thermal Power Engineering, Zhejiang University, Hangzhou 310027, China
| | - Angjian Wu
- State Key Laboratory for Clean Energy Utilization, Institute for Thermal Power Engineering, Zhejiang University, Hangzhou 310027, China
| | - Zhiliang Chen
- Department of Civil and Environmental Engineering, Vanderbilt University, Nashville, TN 37235, USA.
| | - Lei Wang
- State Key Laboratory for Clean Energy Utilization, Institute for Thermal Power Engineering, Zhejiang University, Hangzhou 310027, China
| | - Hong Yu
- State Key Laboratory for Clean Energy Utilization, Institute for Thermal Power Engineering, Zhejiang University, Hangzhou 310027, China
| | - Hao Zhang
- State Key Laboratory for Clean Energy Utilization, Institute for Thermal Power Engineering, Zhejiang University, Hangzhou 310027, China
| | - Aizhong Ruan
- Zhejiang Shengyuan Environmental Testing Technology Co., Ltd., 311899 Shaoxing, China
| | - Xiaodong Li
- State Key Laboratory for Clean Energy Utilization, Institute for Thermal Power Engineering, Zhejiang University, Hangzhou 310027, China
| | - Jianhua Yan
- State Key Laboratory for Clean Energy Utilization, Institute for Thermal Power Engineering, Zhejiang University, Hangzhou 310027, China
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Wang P, Lin X, Xu S, Li X, Ma Y, Liu W, Wu J, Ding J. Simultaneous removal of PCDD/Fs and mercury by activated carbon from a full-scale MSW incinerator in southeast China. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2023; 30:2440-2449. [PMID: 35930157 DOI: 10.1007/s11356-022-22425-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/29/2022] [Accepted: 08/02/2022] [Indexed: 06/15/2023]
Abstract
This study emphasized on the removal performance of polychlorinated-ρ-dibenzodioxins and dibenzofurans (PCDD/Fs) and mercury by different activated carbon injection (ACI) rates from a full-scale (700 t/d) MSW incinerator. The result exhibited that the emission standard of PCDD/Fs and mercury could be met when the ACI rate reached 50 mg/Nm3 and 30 mg/Nm3, respectively. Lower chlorinated PCDD/Fs and PCDFs showed higher removal efficiencies compared with highly chlorinated PCDD/Fs and PCDDs, which could be attributed to the larger competitiveness of highly volatile congeners in AC adsorption than the lower volatile ones. AC turned out to have different adsorption selectivity for CP-routes PCDD/Fs congeners, among which 1379-TCDD was preferred to be absorbed while others exhibited little or poor selectivity for AC adsorption. The removal efficiency of PCDD/Fs was positively correlated with ACI rate at 99% confidence interval with a linear relationship (R2 = 0.98). Also, the outlet concentration of mercury decreased with the increase of ACI rate in a nearly linear function (R2 = 0.96). These results will be meaningful for the rational use of AC for pollutants control.
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Affiliation(s)
- Peiyue Wang
- State Key Laboratory of Clean Energy Utilization, Institute for Thermal Power Engineering, Zhejiang University, Hangzhou, 310027, China
| | - Xiaoqing Lin
- State Key Laboratory of Clean Energy Utilization, Institute for Thermal Power Engineering, Zhejiang University, Hangzhou, 310027, China
| | - Shuaixi Xu
- MOE Key Laboratory of Environmental Remediation and Ecosystem Health, Institute of Environmental Health, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou, 310058, China.
- Zhejiang Development & Planning Institute, Hangzhou, 310000, China.
| | - Xiaodong Li
- State Key Laboratory of Clean Energy Utilization, Institute for Thermal Power Engineering, Zhejiang University, Hangzhou, 310027, China
- Research Institute of Zhejiang University-Taizhou, Taizhou, 318000, China
| | - Yunfeng Ma
- State Key Laboratory of Clean Energy Utilization, Institute for Thermal Power Engineering, Zhejiang University, Hangzhou, 310027, China
| | - Weiping Liu
- MOE Key Laboratory of Environmental Remediation and Ecosystem Health, Institute of Environmental Health, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou, 310058, China
| | - Jiezhen Wu
- Zhejiang Development & Planning Institute, Hangzhou, 310000, China
| | - Jiamin Ding
- Research Institute of Zhejiang University-Taizhou, Taizhou, 318000, China
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He F, Peng Y, Wang F, Dong Y, Chen K, Lu S. Inhibition of PCDD/Fs in a full-scale hazardous waste incinerator by the quench tower coupled with inhibitors injection. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2022; 314:120261. [PMID: 36155219 DOI: 10.1016/j.envpol.2022.120261] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/12/2022] [Revised: 09/03/2022] [Accepted: 09/19/2022] [Indexed: 06/16/2023]
Abstract
The control of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) from the flue gas in hazardous waste incinerators (HWIs) is an intractable problem. To figure out the formation mechanism of PCDD/Fs and reduce the emission, a field study was carried out in a full-scale HWI. Ca(OH)2 & (NH4)H2PO4 or CH4N2S & (NH4)H2PO4 were injected into the quench tower, and the detailed inhibition effect on PCDD/Fs formation by the inhibitors coupled with quench tower was studied. Gas and ash samples were collected to analyze PCDD/Fs. XPS, EDS characterization and Principal component analysis were adopted to further analyze the de novo and precursors synthesis. The PCDD/Fs emissions reduced from 0.135 ng I-TEQ/Nm3 to 0.062 or 0.025 ng I-TEQ/Nm3 after the injection of Ca(OH)2 & (NH4)H2PO4 or CH4N2S & (NH4)H2PO4, respectively. The quench tower was found mainly hindering de novo synthesis by reducing reaction time. CP-route was the dominant formation pathway of PCDD/Fs in quench tower ash. Ca(OH)2 & (NH4)H2PO4 effectively inhibit precursors synthesis and reduce proportions of organic chlorine from 4.11% to 2.86%. CH4N2S & (NH4)H2PO4 show good control effects on both de novo and precursors synthesis by reducing chlorine content and inhibiting metal-catalysts. Sulfur-containing inhibitors can cooperate well with the quench tower to inhibit PCDD/Fs formation and will be effective to reduce dioxins formation in high chlorine flue gas. The results pave the way for further industrial application of inhibition to reduce PCDD/Fs emissions in the HWIs flue gas.
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Affiliation(s)
- Fengyu He
- Institute for Thermal Power Engineering, Zhejiang University, Hangzhou, 310027, China
| | - Yaqi Peng
- Institute for Thermal Power Engineering, Zhejiang University, Hangzhou, 310027, China.
| | - Fei Wang
- Institute for Thermal Power Engineering, Zhejiang University, Hangzhou, 310027, China
| | - Yuhang Dong
- Institute for Thermal Power Engineering, Zhejiang University, Hangzhou, 310027, China
| | - Ken Chen
- Institute for Thermal Power Engineering, Zhejiang University, Hangzhou, 310027, China
| | - Shengyong Lu
- Institute for Thermal Power Engineering, Zhejiang University, Hangzhou, 310027, China
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Chen Z, Lin X, Zhang S, Xiangbo Z, Li X, Lu S, Yan J. Thermal cotreatment of municipal solid waste incineration fly ash with sewage sludge for PCDD/Fs decomposition and reformation suppression. JOURNAL OF HAZARDOUS MATERIALS 2021; 416:126216. [PMID: 34492973 DOI: 10.1016/j.jhazmat.2021.126216] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/26/2021] [Revised: 05/11/2021] [Accepted: 05/23/2021] [Indexed: 06/13/2023]
Abstract
Thermal treatment of municipal solid waste incineration fly ash (FA) is an effective method to detoxicate FA and produce secondary material with good utilization properties, but the high temperature induced migration of carbon, chlorine, and catalytic metals from FA to flue gases can result in a considerable reformation of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs). Herein, two typical fly ashes were thermally cotreated with sewage sludge (SS), respectively, and the decomposition and reformation of PCDD/Fs were systematically investigated. Thermal treatment effectively decomposed PCDD/Fs in all samples to a low level well meeting the reutilization criterion of 50 ng WHO-TEQ g-1. Cleavage of the oxygen bridge was identified as the primary decomposition pathway. Compared to mono-treating FA, cotreating FA with SS resulted in a better CaO-Al2O3-SiO2 ternary system for vitrification and effectively suppressed the reformation of PCDD/Fs in off-gases with inhibition efficiencies up to 96%. Based on the variation of chemical speciation of N, P, and S in SS after thermal treatment, SS appeared to be a S-N-containing inhibitor which passivated catalytic metals to suppress PCDD/Fs synthesis. The better suppression on de novo pathway than on chlorophenol-route identified by monitoring PCDD/F-fingerprints evolution further verified the suppression mechanism of passivating catalytic metals.
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Affiliation(s)
- Zhiliang Chen
- State Key Laboratory for Clean Energy Utilization, Institute for Thermal Power Engineering, Zhejiang University, Hangzhou 310027, China; Department of Civil and Environmental Engineering, Vanderbilt University, Nashville, TN 37215, United States
| | - Xiaoqing Lin
- State Key Laboratory for Clean Energy Utilization, Institute for Thermal Power Engineering, Zhejiang University, Hangzhou 310027, China.
| | - Sheng Zhang
- State Key Laboratory for Clean Energy Utilization, Institute for Thermal Power Engineering, Zhejiang University, Hangzhou 310027, China
| | - Zou Xiangbo
- Guangdong Energy Group Science and Technology Research Institute Co., Ltd., Guangzhou 510630, China
| | - Xiaodong Li
- State Key Laboratory for Clean Energy Utilization, Institute for Thermal Power Engineering, Zhejiang University, Hangzhou 310027, China
| | - Shengyong Lu
- State Key Laboratory for Clean Energy Utilization, Institute for Thermal Power Engineering, Zhejiang University, Hangzhou 310027, China
| | - Jianhua Yan
- State Key Laboratory for Clean Energy Utilization, Institute for Thermal Power Engineering, Zhejiang University, Hangzhou 310027, China
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Ma Y, Wang P, Lin X, Chen T, Li X. Formation and inhibition of Polychlorinated-ρ-dibenzodioxins and dibenzofurans from mechanical grate municipal solid waste incineration systems. JOURNAL OF HAZARDOUS MATERIALS 2021; 403:123812. [PMID: 33264911 DOI: 10.1016/j.jhazmat.2020.123812] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/19/2020] [Revised: 08/18/2020] [Accepted: 08/28/2020] [Indexed: 06/12/2023]
Abstract
This study is carried out in two full-scale (300 t/d) municipal solid waste incinerators (MSWI), focusing on the inhibition effect on polychlorinated-ρ-dibenzodioxins and dibenzofurans (PCDD/F) formation by the Sulfur-, Phosphorus-, and Nitrogen-containing inhibitors. The inhibition efficiencies of total PCDD/F range from 45.77 % to 58.55 %, meanwhile, from 50.1 % to 57.6 % for toxic PCDD/F. X-ray photoelectron spectroscopy results conduct the inhibition effect on the three key factors of PCDD/F formation: catalytic metal, carbon source and chlorine source. Inhibitors can increase the proportion of inorganic chlorine form at the ash surface. The changes of sulfur and phosphorus forms support the inhibition mechanisms of PCDD/F. De novo synthesis is the stable inhibition pathway in this study, meanwhile, the chlorophenols-route and dibenzodioxin and dibenzofuran chlorination also work in some tests. The results are the basics for further industrial application of PCDD/F inhibitors and benefit in controlling the PCDD/F emission from MSWI.
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Affiliation(s)
- Yunfeng Ma
- State Key Laboratory for Clean Energy Utilization, Institute for Thermal Power Engineering, Zhejiang University, Hangzhou 310027, China
| | - Peiyue Wang
- State Key Laboratory for Clean Energy Utilization, Institute for Thermal Power Engineering, Zhejiang University, Hangzhou 310027, China
| | - Xiaoqing Lin
- State Key Laboratory for Clean Energy Utilization, Institute for Thermal Power Engineering, Zhejiang University, Hangzhou 310027, China.
| | - Tong Chen
- State Key Laboratory for Clean Energy Utilization, Institute for Thermal Power Engineering, Zhejiang University, Hangzhou 310027, China
| | - Xiaodong Li
- State Key Laboratory for Clean Energy Utilization, Institute for Thermal Power Engineering, Zhejiang University, Hangzhou 310027, China
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